The pupils should observe the second year's growth of biennials.
They must be carefully watered, and shaded as above directed for Biennials.
Snapdragons may be treated as annuals or biennials, and each has its own difficulty.
Biennials, and also most perennials, must be raised every year to keep up the supply.
Biennials and perennials should be sown before the middle of the month.
Plants are of three classes — annuals, biennials, perennials.
The bark of the annual trees is generally pale; that of the biennials, dark.
The annuals and biennials may be sown in the open early in spring.
As to the time for sowing, see "Annuals," "Biennials," and "Perennials."
Biennials are almost as much care, but in each case there will always be exceptions that are a matter of individual preference.